Form S-1: The 2026 Definition Guide for CFOs and Finance Teams

Form S-1 is the registration statement a U.S. company must file with the SEC before it can legally sell securities to the public. It is the foundational document of any domestic IPO, and for the finance team, it is also the most demanding disclosure project the company will ever undertake. Get it wrong, and the CEO, CFO, and every board member who signed it face civil liability under Section 11 of the Securities Act of 1933.

This guide explains what Form S-1 is, what it must contain, who files it, and what the 2024 revision changed. For the step-by-step filing process, see our practitioner walkthrough. For the confidential submission strategy, see the DRS guide.

What Is Form S-1?

Form S-1 is the default registration statement under the Securities Act of 1933 for all domestic registrants for which no other form is authorized or prescribed. In plain terms: if a U.S. company wants to sell securities to the public and no specialized form applies, it files an S-1.

As the SEC's own instructions state: "This Form shall be used for the registration under the Securities Act of 1933 of securities of all registrants for which no other form is authorized or prescribed, except that this Form shall not be used for securities of foreign governments or political subdivisions thereof or asset-backed securities."

Foreign private issuers use Form F-1 instead. Real estate investment trusts use Form S-11. Companies registering securities in a merger or exchange offer use Form S-4. For a side-by-side comparison, see our registration statement comparison guide.

The S-1 is most commonly associated with IPOs, but it also applies to:

• Follow-on offerings by companies that have been Exchange Act reporters for fewer than 12 months
• SPAC IPOs (with additional disclosure requirements under the SEC's January 2024 final rules, Release No. 33-11265)
• Any domestic company registering securities for the first time when no other form is prescribed

Key takeaway: The S-1 is not a form companies choose. It is the form they use when no other form is available. It is the SEC's default, and it carries the heaviest disclosure burden of any registration statement.

What Does Form S-1 Contain? Part I vs. Part II

The S-1 splits into two distinct parts with different audiences and purposes.

Part I: The Prospectus

Part I is the investor-facing document. It is distributed to potential investors and must contain, under Regulation S-K (17 CFR Part 229):

• Item 101: Business description, including the 2020-amended human capital resources disclosure (what workforce metrics management actually tracks)
• Item 105: Risk factors, specific and tailored to the company. Since the 2020 Regulation S-K amendments (Release No. 33-10825), a risk factor summary is required if the full section exceeds 15 pages
• Item 303: Management's Discussion and Analysis (MD&A), modernized by the 2020 MD&A amendments (Release No. 33-10890), which eliminated the contractual obligations table, made off-balance-sheet discussion principles-based, and added a critical accounting estimates section
• Item 402: Executive compensation, now including pay-versus-performance disclosure (2022, Release No. 34-95607) and clawback policy disclosure (2023, Release No. 34-97243) for non-EGC filers
• Item 202: Description of the securities being registered, per the 2019 final rule (Release No. 33-10622)
• Audited financial statements prepared under U.S. GAAP and audited under PCAOB standards
• Use of proceeds, dilution, and offering price methodology

Note: The Selected Financial Data table (formerly Item 301) was eliminated by the SEC in August 2021. Any S-1 guide that still describes a five-year selected financial data table is describing a requirement that no longer exists.

Part II: Supplemental Information and Exhibits

Part II is filed with the SEC but not distributed to investors. It contains:

• Underwriting agreements and material contracts
• Corporate charter, bylaws, and governance documents
• Legal opinions and auditor consents
• Subsidiary lists
• The description of securities (Exhibit 4.x)

Gaps or inconsistencies between Part II exhibits and Part I prospectus statements are a common source of SEC comment letters.

What Financial Statements Does an S-1 Require?

The S-1 prospectus must include audited financial statements for the two most recent fiscal years (one year for smaller reporting companies), prepared under U.S. GAAP and audited to PCAOB standards, per Regulation S-X (17 CFR Part 210).

Two timing rules that catch finance teams off guard:

• Non-accelerated filers: Interim (unaudited) financial statements are required if the most recent audited period ended more than 134 days before the registration statement's effective date
• Accelerated filers: The threshold tightens to 129 days

This means IPO timing is not just a market window question. It is a financial statement staleness question. A company whose fiscal year ends December 31 that wants to go effective in late summer must have its Q2 interim financials ready, or it cannot proceed. For the full financial statement requirements, see our IPO financial statement requirements guide.

The PCAOB audit requirement is non-negotiable. Many pre-IPO companies discover they have years of financial statements audited under AICPA standards that must be re-audited under PCAOB standards before the S-1 can be filed. That re-audit process takes months and is one of the most common causes of IPO timeline slippage.

Who Must File Form S-1, and Who Is Exempt?

Form S-3 eligibility requires at least 12 months of Exchange Act reporting history and a public float of at least $75 million for primary offerings. Until those thresholds are met, the S-1 is the only option for a domestic registrant. For a detailed comparison, see our S-1 vs. S-3 guide.

What Is Emerging Growth Company Status, and How Does It Change the S-1?

An emerging growth company (EGC) is a company with total annual gross revenues below $1.235 billion in its most recently completed fiscal year, as defined in Section 2(a)(19) of the Securities Act (as adjusted for inflation). EGC status was created by the JOBS Act of 2012 and fundamentally changed the S-1 landscape for most IPO candidates.

EGC status expires at the earliest of:

1. The last day of the fiscal year in which revenues exceed $1.235 billion
2. The last day of the fiscal year following the fifth anniversary of the IPO
3. The date the company has issued more than $1 billion in non-convertible debt in the prior three years
4. The date the company becomes a large accelerated filer

For the S-1 specifically, EGC status provides two major accommodations:

• Reduced financial history: An EGC may omit financial information for historical periods it reasonably believes will not be required at the time of the offering, provided the registration statement is amended to include all required Regulation S-X financials before distributing a preliminary prospectus to investors
• Confidential submission: EGCs may submit a draft registration statement (DRS) for confidential SEC staff review before any public filing

EGCs are also exempt from the pay-versus-performance disclosure requirement under Item 402. For a full breakdown of EGC accommodations, see our emerging growth company status guide.

What Is the Confidential Draft Registration Statement (DRS) Process?

The confidential DRS process allows companies to submit their S-1 to the SEC for staff review without making it public. Originally available only to EGCs under the JOBS Act, the SEC extended confidential submission to all first-time registrants in June 2017, provided the company has not previously filed an S-1 or had a reporting obligation under the Exchange Act in the prior three years. The March 2025 SEC expansion broadened eligibility further.

The key timing rule: the DRS must be publicly filed at least 15 days before the road show begins (or before the requested effective date if there is no road show), per SEC guidance on emerging growth companies.

The strategic advantages are significant:

• The company can work through SEC comment letter rounds without competitors, press, or investors seeing early-stage financials
• Management can test the SEC's reaction to novel business model disclosures or unusual accounting treatments before committing to a public filing
• If market conditions deteriorate, the company can withdraw without any public record of the attempt

For the full DRS strategy and process, see our confidential S-1 filing guide.

What Did the 2024 Form S-1 Revision Change?

The current Form S-1 was revised in July 2024 (SEC 870, 07-24), with an OMB expiry of March 31, 2029. The most striking data point in the revision: the estimated average burden dropped to 160.63 hours per response, down from 667 hours in the January 2016 version. That is a 76% reduction in estimated burden, reflecting the cumulative impact of EGC accommodations, the elimination of Selected Financial Data, and streamlined requirements for smaller filers.

The 2024 revision also explicitly addresses SPAC S-1 filings, noting that if the form is being used to register an offering of a SPAC (as defined in Item 1601(b) of Regulation S-K), additional requirements apply under the January 2024 SPAC final rules.

What Are the Section 11 Liability Implications of Signing an S-1?

This is the governance point that most generic S-1 guides skip entirely.

Under Section 11 of the Securities Act of 1933, every person who signed the registration statement faces potential civil liability if the S-1 contains a material misstatement or omission at the time it becomes effective. The required signatories are not just the company itself. The S-1 must be signed by:

• The principal executive officer (CEO)
• The principal financial officer (CFO)
• The principal accounting officer or controller
• A majority of the board of directors

This broad signing requirement is why the due diligence process for an S-1 is so rigorous, why legal opinions and auditor comfort letters are standard, and why the CFO's personal exposure is real. It is also why the SEC comment letter process, however slow it feels, serves a protective function: it forces the company to defend every material disclosure before the registration becomes effective.

For the comment letter process in detail, see our SEC comment letter walkthrough.

How Is the Registration Fee Calculated?

The S-1 registration fee is calculated under Rule 457 (17 CFR 230.457). Under Rule 457(o), only the title of the class of securities, the proposed maximum aggregate offering price, and the registration fee need appear in the fee table.

The fee rate is set annually by the SEC. For fiscal year 2025 (effective October 1, 2024), the SEC set the rate at $153.10 per $1,000,000 of securities registered. For a $500 million IPO, that translates to approximately $76,550 in registration fees, a rounding error relative to total IPO costs but a required calculation nonetheless.

What Happens After the S-1 Is Filed?

Filing the S-1 is not the end. It is the beginning of the SEC review process.

The SEC's Division of Corporation Finance targets an initial comment letter within 30 calendar days of the first filing. Comment letters are made public on EDGAR 20 business days after the registration statement is declared effective or withdrawn. Multiple rounds of comments are common, particularly for first-time filers. The most frequent comment areas include MD&A (revenue recognition, liquidity, non-GAAP measures), risk factors (specificity and tailoring), and financial statements (segment reporting, related-party transactions).

Companies respond via S-1/A amendments. Once all comments are resolved, the SEC declares the registration statement effective. At that point, the company prices the offering and files the final prospectus on Form 424B4 within two business days of pricing in a firm commitment underwritten offering. The 424B4 is the document actually delivered to investors; the S-1 and its amendments are the regulatory record.

For the full post-filing timeline, see our IPO timeline walkthrough.

ESG and Climate Disclosures in an S-1: Where Things Stand in 2026

This is the question Finrep's ESG audience is asking, and the one most S-1 guides ignore entirely.

The SEC adopted climate disclosure rules in March 2024 (Release No. 33-11275), which would require large accelerated filers and accelerated filers to include climate-related disclosures in registration statements including S-1s. However, as of October 2026, those rules remain subject to ongoing litigation consolidated in the Eighth Circuit, and the SEC has voluntarily stayed their implementation pending judicial resolution.

The practical position for S-1 filers today:

• No mandatory climate disclosure under the SEC's 2024 rules while the stay is in effect
• Voluntary disclosure is common and expected by institutional investors, particularly for companies in carbon-intensive sectors
• Risk factor disclosure about climate-related risks remains required under existing Regulation S-K principles if those risks are material
• Cybersecurity governance disclosures are required under the 2023 cybersecurity rules (Release No. 33-11216), which are in effect and apply to S-1 filers

Companies filing S-1s in 2026 should expect investor and underwriter pressure to include voluntary climate and ESG disclosures even absent a mandatory SEC requirement. The absence of a rule does not mean the absence of market expectation.

FAQ

What is Form S-1 used for? Form S-1 is used to register securities under the Securities Act of 1933 before a U.S. company can sell them to the public. It is most commonly filed for IPOs by domestic companies that do not qualify for the shorter Form S-3.

What is the difference between an S-1 and an S-1/A? The S-1 is the initial registration statement. The S-1/A is an amendment filed in response to SEC comment letters or to update financial statements. Most companies file multiple S-1/A amendments before the registration is declared effective. See our S-1/A walkthrough for detail.

How long does the S-1 review process take? The SEC targets an initial comment letter within 30 calendar days of the first filing. Total time from initial filing to effectiveness typically ranges from 60 to 120 days for a straightforward IPO, longer if the company's business model or accounting is novel.

Who signs the Form S-1? The CEO, CFO, principal accounting officer or controller, and a majority of the board of directors must all sign the S-1. Each signer faces potential Section 11 civil liability for material misstatements or omissions.

Can a private company file an S-1 confidentially? Yes. First-time registrants that have not previously filed an S-1 or had Exchange Act reporting obligations in the prior three years may submit a draft registration statement (DRS) for confidential SEC review. The DRS must be publicly filed at least 15 days before the road show.

What is the registration fee for an S-1? The fee is calculated under Rule 457. At the FY2025 rate of $153.10 per $1,000,000 of securities registered, a $500 million offering carries a fee of approximately $76,550.

Does Form S-1 require climate disclosures in 2026? Not under the SEC's 2024 climate rules, which remain stayed pending litigation. Material climate-related risks must still be disclosed under existing Regulation S-K risk factor principles if they are material to the company.